Burns Management, Rule of Nines & Wound Care

Burn injuries represent severe, multi-system trauma characterized by profound destruction of the cutaneous barrier, massive fluid loss, systemic hypermetabolism, and significant hemodynamic compromise. Effective nursing management requires rapid, accurate assessment of burn depth and Total Body Surface Area (%TBSA), calculated intravenous crystalloid resuscitation, vigilant monitoring of organ perfusion, and expert wound care.

---

1. Pathophysiology of Burn Trauma

Burn injuries produce both localized tissue destruction and a profound systemic inflammatory response syndrome (SIRS).

Local Tissue Zones of Burn Injury (Jackson's Burn Zones)

1. Zone of Coagulation: The central area of the burn where cellular death and tissue necrosis are instantaneous and irreversible due to severe protein denaturation. Requires surgical excision and grafting.
2. Zone of Stasis: The intermediate zone surrounding the zone of coagulation, characterized by compromised microvascular perfusion, capillary stasis, and ischemia. Tissues here are potentially salvageable with prompt, aggressive fluid resuscitation; persistent hypoperfusion or infection converts this zone into irreversible necrosis.
3. Zone of Hyperemia: The outermost periphery characterized by vasodilation and increased microvascular perfusion due to the inflammatory response. This viable tissue consistently recovers unless complicated by severe sepsis or shock.

Systemic Response to Major Burns (> 20% TBSA)

When burns exceed 20% of Total Body Surface Area, local inflammation transforms into an overwhelming systemic hyper-inflammatory cascade:

• Massive Capillary Hyperpermeability: Release of vasoactive mediators (histamine, bradykinin, prostaglandins, leukotrienes, interleukins, and tumor necrosis factor) causes extensive loss of endothelial integrity. This capillary leak extends beyond the burned tissue to unburned skin and visceral capillary beds throughout the entire body.
• Fluid Shifting & Third-Spacing: Plasma proteins (predominantly albumin), water, and intravascular electrolytes pour out of the vascular tree into the interstitial spaces (third-spacing). This reaches its maximum intensity within 8 to 12 hours post-injury and persists for 24 to 36 hours until capillary membranes begin to reseal.
• Hypovolemic Burn Shock & Hemoconcentration: The abrupt reduction in circulating intravascular blood volume produces profound hypovolemia, decreased cardiac output, hypotension, and systemic organ hypoperfusion. Massive fluid transudation leaves red blood cells concentrated within the vascular compartment, resulting in hemoconcentration (elevated hematocrit, often 50–60%).
• Electrolyte Derangements:
  • Hyperkalemia (Immediate / Initial Resuscitation Phase): Massive thermal cellular lysis and tissue destruction dump vast amounts of intracellular potassium into the extracellular fluid. This occurs during the first 24 to 48 hours and can induce lethal cardiac dysrhythmias.
  • Hypokalemia (Later / Diuretic Phase): As capillary integrity returns (after 48 hours), large volumes of fluid shift back into the intravascular space, initiating a major diuretic phase. Potassium is rapidly excreted in the urine, while fluid shifts cause dilutional hypokalemia.
  • Hyponatremia: Trapping of sodium in interstitial fluid third spaces and evaporative losses cause initial hyponatremia.
• Renal Complications: Severe renal hypoperfusion triggers acute prerenal kidney injury. In high-voltage electrical injuries or severe full-thickness burns involving muscle destruction, extensive myoglobinuria and hemoglobinuria develop. In the acidic environment of the renal tubules, free myoglobin precipitates into dense tubular casts, leading to acute tubular necrosis and renal shutdown.

---

2. Classification of Burn Injuries

Burn trauma is classified according to the causative mechanism and the histological depth of tissue damage.

Etiological Mechanisms

• Thermal Burns: Caused by flame, flash, scalding liquids (hot water/oil), or direct contact with hot objects. Scald burns are common in pediatric and elderly populations.
• Chemical Burns: Result from contact with strong acids, alkalis, or organic compounds. Alkalis (e.g., lye, drain cleaners, wet cement) produce liquefactive necrosis and saponify fats, allowing deep and continuous tissue penetration; acids produce coagulative necrosis, which forms a protective eschar. Management: Immediate, copious irrigation with tap water or normal saline for 20 to 30 minutes (neutralizing agents are strictly contraindicated due to exothermic heat-producing reactions).
• Electrical Burns: Result from high-voltage (> 1,000 V) or low-voltage current passing through body tissues. Follows pathways of least electrical resistance (nerves and blood vessels), generating extreme internal thermal energy. Characteristics: Small, deceptive entry and exit cutaneous wounds often mask devastating internal deep-tissue destruction of muscle, tendons, and bone. Complications: Immediate fatal ventricular fibrillation or asystole requires continuous ECG monitoring for at least 24 hours. Massive rhabdomyolysis and myoglobinuria necessitate elevated resuscitation fluid rates.
• Radiation Burns: Caused by ultraviolet radiation (sunburn) or ionizing therapeutic radiation.

Depth of Tissue Destruction

---

3. Assessment of Total Body Surface Area (%TBSA)

Accurate calculation of burned surface area determines fluid resuscitation requirements. Superficial (first-degree) burns like sunburn are excluded from TBSA calculations; only partial-thickness and full-thickness burns are counted.

Wallace's Rule of Nines for Adults

The Rule of Nines divides the adult body surface into anatomical regions representing 9% (or multiples of 9%) of Total Body Surface Area, plus 1% for the perineum:

Pediatric Sizing: Lund and Browder Chart

The adult Rule of Nines cannot be applied to infants and young children because an infant's head is proportionally much larger (~18% in a newborn) and the lower extremities are proportionally smaller (~14% each). The Lund and Browder Chart provides age-adjusted percentage allocations for accurate pediatric sizing.

Palmar Method

For small, scattered, or patchy burn areas, the Palmar Method is utilized: the patient's entire hand (the palm plus all five digits extended) represents approximately 1% of that patient's Total Body Surface Area.

---

4. Fluid Resuscitation Protocols

Intravenous crystalloid resuscitation is the cornerstone of burn shock management. Resuscitation is indicated for any adult with burns exceeding 20% TBSA (or > 10% TBSA in children and the elderly).

The Parkland (Baxter) Formula

The international standard for initial fluid resuscitation during the first 24 hours post-injury is the Parkland Formula:

$\text{Total 24-Hour Resuscitation Fluid (Ringer's Lactate)} = 4\text{ mL} \times \text{Body Weight (kg)} \times \text{\%TBSA Burn}$

Fluid of Choice: Ringer's Lactate (RL) is the preferred crystalloid because its electrolyte composition closely resembles human plasma, and its lactate component is metabolized by the liver into bicarbonate, helping counteract metabolic acidosis. Normal Saline ($0.9\%\text{ NaCl}$) is avoided in large volumes because its high chloride concentration ($154\text{ mEq/L}$) induces hyperchloremic metabolic acidosis.

Administration Schedule

The total calculated volume for the first 24 hours is divided into two distinct delivery intervals:

1. First 8 Hours: Administer 50% (one-half) of the total 24-hour volume.
   • CRITICAL RULE: The 8-hour window is timed from the exact time of the burn injury, NOT the time of hospital or emergency department arrival. Any fluid administered during pre-hospital transport is subtracted from this 8-hour total.
2. Next 16 Hours: Administer the remaining 50% (one-half) of the total calculated volume over the subsequent 16 hours (infused at a steady rate, typically 25% over the second 8 hours and 25% over the third 8 hours).

Worked Step-by-Step Calculation Example

Clinical Scenario: A 70 kg adult male sustains flame burns covering his entire anterior chest, entire anterior abdomen, and the entire right upper extremity at 10:00 AM. He arrives at the trauma burn center at 12:00 PM (noon). Calculate the total 24-hour fluid requirements and determine the hourly infusion rates.

1. Determine %TBSA:
   • Anterior trunk (anterior chest 9% + anterior abdomen 9%) = 18%
   • Entire right upper extremity = 9%
   • $\text{Total \%TBSA} = 18\% + 9\% = 27\%$
2. Calculate Total 24-Hour Volume: $\text{Total Volume} = 4\text{ mL} \times 70\text{ kg} \times 27 = 7{,}560\text{ mL of Ringer's Lactate}$
3. Calculate First 8-Hour Volume: $\text{Volume for First 8 Hours} = 50\% \times 7{,}560\text{ mL} = 3{,}780\text{ mL}$
4. Calculate Hourly Rate for First 8 Hours (Accounting for Elapsed Time):
   • Time of injury was 10:00 AM; the first 8-hour window closes at 6:00 PM.
   • Patient arrived at 12:00 PM; 2 hours have already elapsed.
   • The entire 3,780 mL must be infused across the remaining 6 hours: $\text{Infusion Rate} = \frac{3{,}780\text{ mL}}{6\text{ hours}} = 630\text{ mL/hour}$
5. Calculate Remaining 16-Hour Volume and Rate:
   • Remaining volume = $3{,}780\text{ mL}$
   • Infused across 16 hours (from 6:00 PM to 10:00 AM the next day): $\text{Infusion Rate} = \frac{3{,}780\text{ mL}}{16\text{ hours}} = 236.25\text{ mL/hour} \approx 236\text{ mL/hour}$

Monitoring Resuscitation Adequacy

While formulas provide initial infusion estimates, clinical fluid titration must be guided strictly by individual physiological endpoints. Hourly urine output via an indwelling Foley catheter is the gold standard indicator of organ perfusion adequacy:

• Adult Thermal Burns Target: 0.5 to 1.0 mL/kg/hour (approximately 30 to 50 mL/hour).
• Pediatric Burns Target (< 30 kg): 1.0 to 1.5 mL/kg/hour.
• Electrical Burns Target (with Myoglobinuria): 75 to 100 mL/hour in adults until the urine visibly clears from dark burgundy/tea color to light straw yellow. Intravenous sodium bicarbonate is co-administered to alkalinize the urine ($pH > 6.5$), preventing myoglobin crystallization in renal tubules.
• Under-resuscitation Risks: Acute kidney injury, conversion of the zone of stasis to necrosis, hypovolemic collapse.
• Over-resuscitation Risks ("Fluid Creep"): Pulmonary edema, cerebral edema, airway compromise, and abdominal compartment syndrome (intra-abdominal pressure > 20 mmHg requiring decompressive laparotomy).

---

5. Critical Airway & Surgical Emergencies in Burns

Inhalation Injury

Inhalation trauma is the leading cause of early mortality in burn patients. Suspect inhalation injury whenever burns occur in an enclosed space.

• Clinical Hallmarks of Inhalation Injury:
  • Facial burns, scorched lips, singed eyebrows and vibrissae (nasal hairs)
  • Soot, carbonaceous deposits in the mouth, pharynx, or sputum
  • Brassy cough, hoarseness, altered voice pitch
  • Stridor, wheezing, tachypnea, air hunger, intercostal retractions
  • Erythema and blistering of the oral mucosa
• Carbon Monoxide (CO) Poisoning: Carbon monoxide binds hemoglobin with an affinity > 200 times that of oxygen, forming carboxyhemoglobin (COHb) and shifting the oxyhemoglobin dissociation curve to the left. Crucial Point: Standard pulse oximetry cannot distinguish oxyhemoglobin from carboxyhemoglobin, giving a falsely normal or elevated $SpO_2$. Classic "cherry-red" skin is a late, postmortem sign. Treatment: Immediately administer 100% oxygen via a tight-fitting non-rebreather mask (reduces COHb half-life from 4–5 hours on room air down to 45–60 minutes) or hyperbaric oxygen.
• Nursing Priority: Rapid airway assessment. Upper airway edema peaks between 24 and 48 hours. If any clinical signs of inhalation injury or stridor are present, the definitive intervention is early prophylactic endotracheal intubation before progressive laryngeal edema completely occludes the glottic aperture.

Circumferential Burns: Escharotomy vs. Fasciotomy

Full-thickness burns produce tough, leathery, non-elastic eschar. As fluid resuscitation expands the interstitial space, this rigid eschar functions like a constrictive tourniquet:

• Thoracic Circumferential Burns: Severely restrict chest wall excursion, producing high peak airway pressures on mechanical ventilation, hypoventilation, hypercapnia, and hypoxemia.
• Extremity Circumferential Burns: Constrict vascular flow, leading to increased intracompartmental pressures, paresthesias, pallor, severe ischemic pain, coldness, delayed capillary refill, and progressive loss of peripheral distal arterial pulses.
• Escharotomy: A surgical emergency bedside procedure. Linear incisions are made through the insensitive full-thickness burn eschar down into the subcutaneous fat layer, releasing mechanical constriction and immediately restoring thoracic expansion or distal extremity perfusion. Because the burned eschar is necrotic and insensate, general anesthesia is not required, and bleeding is typically minimal.
• Fasciotomy: An extensive surgical procedure performed in the operating room under anesthesia, where incisions are carried deeply through the investing muscle fascia. Indicated when deep muscle compartment pressures remain elevated (> 30 mmHg) despite full escharotomy, a frequent requirement in high-voltage electrical injuries.

---

6. Wound Healing Principles & Pressure Injury Staging

Phases of Wound Healing

1. Hemostasis (Immediate): Platelet aggregation, intrinsic/extrinsic coagulation activation, and fibrin clot meshwork formation to control hemorrhage.
2. Inflammatory Phase (Days 0 to 4): Neutrophils arrive first to phagocytose bacteria, followed by macrophages (the master orchestrators of repair), which release cytokines, debride dead cellular material, and stimulate angiogenesis.
3. Proliferative Phase (Days 4 to 21): Marked by granulation tissue formation (highly vascular, granular, beefy-red tissue composed of new capillaries and fibroblasts). Fibroblasts synthesize collagen (principally Type III). Wound contraction occurs via myofibroblasts, and re-epithelialization seals the surface.
4. Maturation / Remodeling Phase (Day 21 to 1–2 Years): Type III collagen is systematically replaced by stronger Type I collagen. Collagen bundles reorganize and cross-link along lines of tension, increasing wound tensile strength up to a maximum of 80% of original uninjured skin.

Types of Wound Closure (Healing Intentions)

• Primary Intention (First Intention): Clean surgical incisions with clean, straight edges neatly approximated by sutures, staples, or surgical glue. Minimal tissue loss; rapid healing with minimal granulation and a thin, hairline scar.
• Secondary Intention: Wounds involving extensive tissue loss, irregular margins, or severe contamination (e.g., pressure ulcers, open infected burns). Wound edges cannot be approximated; the wound is left open and heals slowly by filling with granulation tissue from the base upward, followed by wound contraction and epithelial migration. Results in prolonged healing, high infection risk, and broad, prominent scarring.
• Tertiary Intention (Delayed Primary Closure): Contaminated, infected, or heavily exudative wounds deliberately left open for 3 to 5 days while receiving antimicrobial therapy and wound care. Once the bioburden is controlled, edema resolves, and healthy granulation tissue appears, the wound margins are surgically approximated and closed. Combines elements of secondary granulation with primary surgical closure.

Pressure Injury Staging (NPIAP, formerly NPUAP / EPUAP Guidelines)

A pressure injury is localized damage to the skin and underlying soft tissue, usually over a bony prominence (sacrum, ischial tuberosities, greater trochanters, heels), resulting from prolonged pressure or pressure combined with shear:

Pressure Injury Risk Assessment: The Braden Scale

The Braden Scale assesses six clinical subscales: Sensory Perception (1–4), Moisture (1–4), Activity (1–4), Mobility (1–4), Nutrition (1–4), and Friction/Shear (1–3). Total scores range from 6 to 23; lower scores indicate higher risk. A score of ≤ 16 (or ≤ 18 in elderly populations) classifies a patient at significant risk for pressure injury development, triggering immediate preventive protocols.

Evidence-Based Preventive Interventions

• Repositioning: Turn and reposition bedbound patients at least every 2 hours; reposition chair-bound patients every 1 hour (teach self-repositioning every 15 minutes). Utilize a 30-degree lateral tilted position (supported by pillows) rather than direct 90-degree lateral positioning to avoid direct ischemic compression on the greater trochanters and sacrum.
• Support Surfaces: Utilize pressure-redistributing dynamic air mattresses or alternating-pressure low air loss surfaces; elevate heels off the mattress surface ("float the heels") using pillows or dedicated heel-suspension boots.
• Moisture Management & Skin Care: Keep skin clean and dry. Cleanse promptly after incontinence episodes using mild, pH-balanced cleansers; apply barrier creams (dimethicone, zinc oxide) to shield skin from maceration. Avoid vigorous massage over bony prominences, which fractures delicate capillary networks.
• Nutritional Support: Ensure adequate caloric intake (30–35 kcal/kg/day) and high protein intake (1.25 to 1.5 g/kg/day) to support tissue repair; supplement with Vitamin C (collagen synthesis) and Zinc (epithelialization and immune function).